Thermal Mass Flow Meters for Oil & Gas Applications

Beyond traditional oil and gas extraction techniques, the Oil & Gas Industry has been booming in the United States and around the world since the demand for shale oil has led to horizontal fraction drilling all over the world and even in several regions of the U.S. This drilling is happening both on and offshore to tap into vast quantities of resources trapped in the porous shale deposits deep underground and under the seabed. The flowback from shale oil plays has many different components that must undergo a process of separation in order to isolate the resources for use. Once separated, the byproducts are often stored in tanks before being transported for distribution and sale.

Thermal mass flow meters have been used to measure tank vent and flash gas during storage. VOC emissions from these tank batteries are required to be reported for regulatory purposes. The accurate monitoring of leaks from these tanks is another common use of thermal mass flow meters.

Thermal Mass Flow Meters
(Fox Thermal)

The flowback from fracking well heads must go through separators in order to separate the
water/chemical solution from the oil and gas components that the water has forced out of the shale formations. The gases processed by the separators exit the separator unit from its own outlet that must be accurately measured for accounting and allocation purposes. Furthermore, flow of water, oil, and gases from the separator equipment must be measured to determine how productive the resources from the gas well head are. Over time, the well heads produce less and less gases and owners must determine when to decommission them.

Due to the often remote locations of these gas wells, there are not always local utilities available to power the equipment needed at the well site. Fuel gas to the equipment is needed to measure and monitor consumption.

Exhaust and vent gas from compressor packing cases is required to be monitored for environmental impact.

Some common gases and applications:

• Compressor Packing Case Exhaust Flow Measurement
• Greenhouse Gas Emissions Monitoring Flow Meters
• Continuous Emissions Monitoring
• Flow Meters for EPA and Other Emissions Regulations and Protocols
• GHG Flow Meter
• Sub meters for Natural Gas Measurement
• Tank Vent / Flash Gas Station Monitoring
• Natural Gas Totalizers
• Methane Flow Measurement
• Propane Flow Measurement
• 40 CFR Part 60 Subpart OOOO Reporting
• 40 CFR Part 98 Subpart W Reporting
• CO2e Reporting
• Flare and Combustor Gas Measurement
• Separator Gas Measurement
• Vapor Recovery Unit (VRU) Gas Measurement
• Fuel & Combustion Gas Measurement
• Other Pure and Mixed Gas Applications

For more information on applying thermal mass flow meters in the oil and gas industry, contact Classic Controls at 863-644-3642 or visit https://classiccontrols.com.

Case Study On Thermal Flow Meter Calibration For Natural Gas Service

The Importance of Gas Composition and Calibration and their Effects on Flow Meter Accuracy

Errors associated with the calibration of flow meters for natural gas service can be costly but can also be mitigated using an advanced flow meter design that allows field-adjustment of the natural gas composition without loss of accuracy.

This outstanding case study, courtesy of Fox Thermal Instruments, discusses the importance of gas composition and calibration and their effects on flow meter accuracy.

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DOWNLOAD THE CASE STUDY FROM THE CLASSIC CONTROLS WEB SITE HERE

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For more information, contact Classic Controls.
https://classiccontrols.com
863.644.3642

New Thermal Mass Flow Meter

The new model FT4A thermal mass flowmeter, shown
inserted in process pipe.
Courtesy Fox Thermal Instruments

Fox Thermal Instruments, manufacturer of thermal technology based mass flow instruments for industrial process measurement, has introduced a new more advanced product providing the accuracy and reliability users expect from Fox, along with some new features extending the ease of use and applicability of the instrument.

The basic operation involves measuring flow in relation to its heat dissipating effect on a temperature sensor. Higher mass flow produces a higher rate of heat transfer.

The mass flow measurement instruments are very popular for several reasons. They have no moving parts, have a fairly unobstructed flow path, are accurate over a wide range of flow rates, calculate mass flow rather than volume, measure flow in large or small piping systems, and do not need temperature or pressure compensation. While most thermal flow meters are used to measure flowing gas, some also measure flowing liquids.

The new model FT4A incorporates the latest feature updates and technology advancements. More information can be found in the datasheet provided below. Share your gas flow measurement challenges with instrumentation specialists. Combine your own process experience and knowledge with their product application expertise to develop effective solutions.

New Thermal Mass Flow Meter From Fox Instruments from Classic Controls, Inc.

Thermal Mass Flowmeters

Thermal dispersion mass flow meters provide an accurate means of mass flow measurement with no moving parts and little or no encroachment on the media flow path. There are a number of different configurations to be found among various manufacturers, but all function in basically the same manner.

Two sensors are exposed to the heat transferring effect of the flowing media. When the media composition is known, the mass flow can be calculated using the meter reading and the pipe cross sectional area. One of the flow meter sensors is heated, the other is allowed to follow the media temperature as a reference. The heat dispersion from the heated sensor is measured and used to calculate mass flow.

Some positive attributes of thermal dispersion flow meters:

• In-line and insertion configurations available to accommodate very small to large pipe sizes
• Rugged Construction
• No moving parts
• Measure liquid or gas in a wide range of applications
• Measurement not adversely impacted by changes in pressure or temperature
• Wide range of process connections 
• In-line versions provide unobstructed flow path
• Wide turndown suitable for extended flow range
• Flow rate and totalized flow
• 4-20 mA output interfaces easily with other instruments and equipment

Share all your process measurement challenges and requirements with product application specialists, combining your process knowledge with their product application expertise to develop effective solutions.

Thermal Flowmeters with Constant Temperature Differential (∆T) Technology to Measure Mass Flow Rate of Air and Gases

Thermal Flow Meter
Sensor
Fox Thermal Instruments

Thermal flow meters use a constant temperature differential (∆T) technology to measure mass flow rate of air and gases. The thermal mass flow sensor consists of two Resistance Temperature Detectors (RTD’s). The sensor elements are constructed of a reference grade platinum wire wound around ceramic mandrels that are inserted into stainless steel or Hastelloy tubes.

The reference RTD measures the gas temperature. The instrument electronics
heat the mass flow sensor, or heated element, to a constant temperature and measures the cooling effect of the gas flow. The electrical power required to maintain a constant temperature differential is directly proportional to the gas mass flow rate. The microprocessor then linearizes this signal to deliver a linear 4 to 20mA signal.

One manufacturer, Fox Thermal Instruments, implements a

technology they call the Power Pro™ Sensor. Their sensor operates at a higher power level than other competitive thermal technologies, providing better response time and wider turndown. When compared to a typical differential pressure type flow meter, as shown to the right, the Power Pro™ Sensor offers better low flow or low end sensitivity. The Power Pro™ Sensor also provides exceptional accuracy at high velocities - up to 50,000 SFPM air.

The Fox DDC-Sensor™ is a new state of the art sensor technology used in the Fox Model FT1 Thermal Gas Flow Meter. The DDC-Sensor™, a direct digitally controlled sensor that is interfaced directly to the FT1 microprocessor for more speed and programmability.

Like the Power Pro™ Sensor, the DDC-Sensor™ accurately responds to changes in process variables (gas flow rate, pressure, and temperature) which are used by the microprocessor to determine mass flow rate, totalized flow, and temperature.

In addition to measuring flow, the DDC-Sensor™ provides a technology platform for calculating accurate gas correlations. The FT1 correlation algorithms allow the meter to be calibrated on a single gas in the factory while providing the user the ability to select other gases in the Gas-SelectX® gas menu. Fox’s Model FT1 with its DDC-Sensor™ and state-of-the-art correlation algorithms provide an accurate, multi-gas capable thermal flow meter for gas applications.

Thermal Mass Flowmeter and Temperature Transmitter from Classic Controls, Inc.